3 flashes
Easy Fix
Goodman · HVAC Systems (AC, Furnaces & Heat Pumps)
Pressure Switch Stuck Open
Quick Answer
Error code 3 flashes on your Goodman HVAC Systems (AC, Furnaces & Heat Pumps) means: Pressure Switch Stuck Open. This is usually fixable — see the step-by-step guide below.
Likely Causes
How to Fix It
1
Inspect flue pipe and intake for blockages such as ice, debris, or animal nests
2
Check the pressure switch hose for cracks, kinks, or disconnections
3
Verify the inducer motor starts when a heating call is initiated
4
Clear the condensate drain if blocked using compressed air or a wet-dry vacuum
5
Measure draft pressure at the switch port with a manometer and compare to the switch rating
Pro Tip
This is a common issue that most users can resolve without specialized tools. Try the first step before moving on to more complex solutions.
Parts You May Need
Pressure switch
Pressure switch tubing
Inducer motor
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